Vaisala DMT152 - Manual (Page 39)

Chapter 5 ________________________________________________________ Serial Line Operation
VAISALA ________________________________________________________________________ 37
Configuring Analog Outputs
The DMT152 has two analog output channels. These channels can
function either as normal measurement channels, or produce an ON/OFF
output if the measurement exceeds a given alarm level (limit alarm) or if
the measurement reading is frozen (for example, during sensor purge).
- In the normal operation mode, a channel outputs voltage or current
that corresponds to the reading of the selected quantity.
- In the ON/OFF output mode, a channel outputs a specified voltage or
current level. This mode is used by the limit alarm and the purge
status alarm.
- In the LED alarm output mode, the channel outputs operation voltage
for the LED cable. The LED will light up to indicate a frozen
measurement output which is typically caused by transmitter start-up
or sensor purge. The LED will blink at approximately 0.5 Hz if the
malfunction alarm is active. The LED will not light up for the limit
alarm.
Additionally, DMT152 has a malfunction alarm that is always enabled in
normal operation mode. The malfunction alarm can also be enabled for a
channel in ON/OFF output mode. See section Malfunction Alarm on
page 41.
When the transmitter is ordered from Vaisala, the modes are configured
as specified in the order form. You can change the operation settings
after delivery using the AMODE command: